Piano-keyboard.



C. MAHLKE.

PIANO KEYBOARD.

APPLIGATIONIILED JAN.23,1913.

Patented Apr. 21, 1914 179A {3g/V9 BBBHBESEQ www@ um Nonni-n co..

UNITED STATES PATENT OFFICE.

CONRAD MAHLKE, OF ELBING, GERMANY.

PIANO-KEYBOARD.

To all whom t may concern:

Be it known that I, CONRAD MAHLKE, a subject of the King of Prussia, residing at Elbing, Germany, have invented certain new and useful Improvements in Piano-Keyboards, of which the following is a specification.

This invention relates to an improved keyboard for musical instruments, and has for its object to obtain a double octave manual within a single octave compass so that two octaves may be brought within the compass of one hand, thereby enabling each hand to control two octaves simultaneously while enabling the player, when desired, to strike the upper and lower notes of an octave simultaneously with a single linger.

According to the present invention the keys are of equal length and are arranged in a. single row in chromatic order over the whole length of the key-board so as to constitute one manual, each key consisting of a pair of levers arranged side by side at the front but diverging toward the rear, each lever carrying at the front two finger pieces projecting over its companion lever and alternating with and tting between the finger pieces thereof, the four linger pieces being arranged in line from front to rear and in stepwise manner. One lever of each of these pairs of levers is adapted to control the lower note of the octave while the other lever of the pair controls the upper note of the octave. The linger pieces are each provided with al horizontal upper surface terminating at the front in a downwardly inclined surface and terminating at the rear in a correspondingly upwardly inclined surface, so that when the player strikes the horizontal surface, the note corresponding to that particular key will be struck, whereas when the player presses his finger upon the inclined rear portion of the one finger piece and inclined front surface of the next rear linger piece simultaneously, both the upper and lower notes of the octave will be struck.

In order that the invention may be more clearly understood reference is made to the accompanying drawings showing part of a key-board constructed according to the present invention, by way of example.

Figure l is a plan of the key-board and levers, and Fig. 2 is a side view thereof, while Fig. 3 is a plan view showing two of the levers separated. Fig. 4 is a front view Specification of Letters Patent.

Application filed January 23, 1913.

Patented Apr. 21, 1914. serial No. 743,818.

of the key-board. Fig. 5 is a sectional view on the line X-X of Fig. 2.

Each key, as already described, has two levers a and arranged in juxtaposition at their forward ends and diverging toward the rear. The lever a, as may readily be seen in Fig. 2, is cut out at its forward upper part at a and a2 respectively, while the lever l) is correspondingly cut out at l/ and b2. Mounted in the recesses a and a2 of the lever a are linger pieces c and d respectively, these linger pieces having side lugs c and d respectively, overlapping the adjacent lever o. Similarly mounted in the recess of the lever Z) is a linger piece e, while the upper palt of the lever l) is formed into a similar finger piece f, these linger pieces e and f having' similar projecting lugs c and so as to overlap the adjacent lever a. The width of the linger pieces c, (Z, e and f is preferably equal to that of one of the levers a. These linger pieces are, however, arranged centrally between the levers a and Z2 so as to be in line with one another in stepwise manner, as clearly seen in Figs. l and 2.

The finger pieces corresponding to the sharps or flats are preferably constructed of black ivory or other suitable composition in order to distinguish them` from the other keys in the usual manner, but it will be noted that both the black and white keys are of equal length, and are arranged in a single row in chromatic order over the whole length of the keyboard, so as to constitute only one manual as seen in Fig. l, each key having four separate fingerpieces c, (l, e, and f, forming rows of nger pieces, each row being arranged in chromatic order, a space (7 being left between the adjacent finger pieces of each row, as may be seen in Figs. i and 5.

The levers a and are pivoted at it upon a suitable cross-bar c', and the rear part of the levers a and is guided in its oscillating movement by a xed pin 7c working in Slots Z in the levers a and l). The rear ends of the levers a and l) coact with lower and upper lugs m and m2 of a block mi pivoted at n. to a fixed cross-bar o, these blocks m, during' their oscillation, actuating the hammer mechanism in the usual manner.

As will readily be seen from Fig. l of the drawings, the lever a of each pair of levers a and b is adapted to actuate the block m corresponding to the lower note of the octave, while the other lever Z) of the pair is adapted to actuate the block m corresponding to the upper note of the oct-ave. The levers Z) cross over the levers a so as to prevent actuation of the levers Z) on the oscillation of the levers a.

It will be noted that the linger pieces e and l of the lever a alternate with the finger pieces e and of the lever Z) and that the finger pieces c and can be depressed within the recesses a and a2 of the lever a without depressing the lever a, while the finger pieces c and Z of the lever a may be depressed within the recesses b and b2 of the lever b without depressing the lever Z9.

Each finger piece is provided with a hori- Zontal surface p, a front downwardly inclined surface p and a rear correspondingly inclined surface p2, thus, when the player applies his finger to the horizontal surface p of one of the linger pieces, only the corresponding lever will be depressed, whereas when the player places his finger simultaneously upon, say the front portion 2) of the finger piece c and the rear portion p2 of the linger piece d, both levers a and Z) will be simultaneously depressed. lt follows, of course, that the same effect will take place if the inclined surfaces of the keys c and j or e and c are depressed and that by the simultaneous depression of the levers e and Z) both the upper and lower notes of the octave will be struck.

I claim:

l. A musical instrument having a keyboard consisting of two sets of key-levers grouped in pairs at the front so that the twenty-four keys of two octaves are grouped in the space of a single octave, comprising a plurality of pairs of key-levers extended to the front, the levers of each pair being juxtaposed at their forward parts to form keys of equal length and diverging toward the rear, the levers of each pair corresponding respectively to the upper and lower notes of the same octave, and linger-pieces on each of said levers, the finger-pieces of each pair being in alinement with each other transversely of the keyboard so that the lingerpieces of each set 0f 12 keys are arranged in chromatic order in a single row.

2. A musical instrument having a keyboard consisting of two sets of key-levers grouped in pairs at the front so that the Ql1 keys of two octaves are grouped in the space of a single octave, comprising a plurality of pairs of key-levers extended to the front, the levers of each pair being juxtaposed at their forward parts to form keys of equal length and diverging toward the rear, the levers of each aair corresponding respectively to the upper and lower notes of the same octave, and linger-pieces on each of said levers, the finger-pieces of each pair being in alinement with each other transversely of the keyboard and arranged in stepwise relation to each other so that the finger-pieces of each set of l2 keys are arranged in chromatic order in a single row.

3. A musical instrument having a keyboard with two sets of key-levers grouped in pairs at the front so that the 241: keys of two octaves are grouped in the space of a single octave, comprising a plurality of pairs of key-levers extended to the front, the levers of each Jair being juxtaposed at their forward parts to form keys of equal length and diverging toward the rear, the levers of each pair corresponding respectively to the upperl and lower notes of the same octave, said levers having stepped recesses at their forward ends, and finger-pieces mounted in said stepped recesses, the finger-pieces of each pair being in alinement with each other transversely of the keyboard and the lingerpieces of one lever alternating with the finger-pieces of the other lever of said pairs of levers.

4. A musical instrument having a keyboard consisting of two sets of key-levers grouped in pairs at the front so that the 24 keys of two octavos are grouped in the space of a single octave, comprising a plurality of pairs of key-levers, extended to the front, the levers of each pair being juxtaposed at their forward parts to form keys of equal length and diverging toward the rear, the levers of each pair corresponding respectively to the upper and lower notes of the same octave, and finger-pieces on each of said levers, the linger-pieces of each pair being in alinement with each other' transversely of the keyboard and ar y'anged in stepwise relation to each other and having a horizontal upper surface terminating at the front in a downwardly inclined surface and at the rear in a correspondingly upwardly inclined surface.

5. A musical instrument having a keyboard with two sets of key-levers grouped in pairs at the front so that the 24: keys of two octaves are grouped in the space of a single octave, comprising a plurality of pairs of key-levers extended to the front, the levers of each pair being juxtaposed at their forward parts to form keys of equal length and diverging toward the rear, the levers of each pair corresponding respectively to the upper and lower notes of the same octave, said levers having stepped recesses at their forward ends, and fingerpieces mounted in said stepped recesses, the finger-pieces of each pair being in alinement with each other transversely of the keyboard and the finger-pieces of one lever alternating with the finger-pieces of the other lever of said pairs of levers, said linger-pieces having a horizontal upper surface terminating at the front in a downwardly inclined surface and at the rear in a correspondingly upwardly inclined surface.

musical instrument having a keyboard with two sets of key-levers grouped in pairs at the front so that the 24 keys of two octaves are grouped in the space of a single octave, comprising a plurality of pairs of key-levers extended to the front, the levers of each pair being juxta osed at their forward parts to form keys o equal length and diverging toward the rear, the diverging end of one of each of said pairs of levers being raised above the other lever of said pairs, means for pivotally mounting and guiding said levers, finger-pieces on each of said levers, the inger-pieces of each pair being in alinement with each other, transversely of the keyboard and a multiplicity of pivoted blocks each having a pair of forward recesses receiving the rear ends of said levers.

7. kA musical instrument having a keyboard with two sets of key-levers grouped in pairs at the front so that the 24 keys of two octaves are grouped in the space of a single octave, comprising a plurality of pairs of key-levers extended to the front, the levers of each pair being juxtaposed at their forward parts to form keys of equal length and diverging toward the rear, the diverging end of one of said pairs of levers being raised above the other lever of said pairs, means for pivotally mounting and guiding said levers, said levers having stepped recesses at their forward ends, and nger-pieces mounted in said stepped recesses, the nger-pieces of each pair being in alinement with each other transversely of the keyboard and the finger-pieces of one lever alternating with the linger-pieces of the other lever of said pairs of levers, and a multiplicity of pivoted blocks having apair of forward recesses receiving the rear ends of said levers.

8. A musical instrument having a keyboard with two sets of key-levers grouped in pairs at the front so that the 24: keys of two octaves are grouped in the space of a single octave, comprising a plurality of pairs of key-levers extended t0 the front, the levers of each pair being juxtaposed at their forward parts to form keys of equal length and diverging toward the rear, the diverging end of one of said pairs of levers being raised above the other lever of said pairs, means for pivotally mounting and guiding said levers, said levers having stepped recesses at their forward ends, and fingerpieces mounted in said stepped recesses, the finger-pieces of each pair being in alinement with each other transversely of the keyboard and the nger-pieces of one lever alternating with the finger-pieces of the other lever of said pairs of levers, said finger-pieces having a horizontal upper surface terminating at the front in a downwardly inclined surface and at the rear in a correspondingly upwardly inclined surface, and a multiplicity of pivoted blocks having a pair of forward recesses receiving the rear ends of ysaid levers.

In testimony whereof I affix iny signature in presence of two witnesses.

CONRAD MAHLKE.

Witnesses M. HAUNKE, D. SOHU'LTZ.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C. 

